Apparatus comprising a multi-lumen tube

ABSTRACT

The present invention relates to an apparatus comprising at least one multi-lumen tube, wherein the tube has a first group of lumens and a second group of lumens wherein the lumens of the second group are arranged around the lumen(s) of the first group, and wherein the lumen(s) of the first group serve the transportation of at least one first fluid, and wherein the lumens of the second group are filled with at least one functional fluid, wherein the apparatus furthermore comprises at least one actuator which is in communication with at least one of the second lumens and is configured such that at least one property of the functional fluid can be changed by means of the actuator.

The present invention relates to an apparatus having at least one multi-lumen tube.

The use of multi-lumen tubes is known, for example, from the area of catheter technology.

As part of extracorporeal blood treatment, such as in dialysis, one major aspect is that a kinking of the tubes used has to be prevented in order not to put the patient and the success of the treatment at risk. To date, a check of the tubes with respect to kinking took place by a visual check by the user or by the determination of unusual treatment parameters such as unusual pressure values.

It is the underlying object of the present invention to further develop an apparatus of the initially named kind such that it allows a target-oriented use of the tube and in particular makes possible the prevention of a kink state of the tube.

This object is achieved by an apparatus having the features of claim 1.

Provision is accordingly made that the multi-lumen tube has a first group of lumens and a second group of lumens, wherein the lumen(s) of the second group is/are arranged around the lumen(s) of the first group, wherein the lumen(s) of the first group serve(s) the transportation of a fluid, and wherein the lumens of the second group are filled with at least one functional fluid. Provision is furthermore made that the apparatus comprises at least one actuator which is in communication with at least one of the second lumens and which is configured such that at least one property of the functional fluid can be changed by means of the actuator.

This property of the functional fluid can, for example, be its pressure. If it is found that the tube is kinked, the pressure of the functional fluid in at least one lumen of the second group can be increased, which counteracts a kinking of the tube. On or after a kinking has taken place, the kinking can thus be terminated by pressure modulation in the outer lumen(s) without the medium to be transported having to be influenced in the lumen of the first group.

The medium to be transported can, for example, be a bodily fluid and can in particular be blood or also a treatment fluid and in particular a dialysis solution.

The present invention relates to an apparatus whose at least one first lumen is filled with a fluid and to an apparatus whose at least one first lumen is empty and is to be filled with a fluid to be transported.

The procedure of preventing the kinking by pressure modulation is an exemplary possibility of the use of the apparatus in accordance with the invention, but the invention is not restricted thereto.

The lumen(s) of the first group, that is the inwardly disposed lumen(s), can be configured by the pressure action in the outer lumen(s), i.e. the lumen(s) of the second group, such that the wall thickness of said lumen(s) of the first group can be reduced since a sufficient mechanical stability is already achieved by the outwardly disposed lumens.

A material saving is thus possible since the demands on the pressure stiffness are reduced accordingly.

The phrases that “the lumen(s) of the second group is/are arranged around the lumen(s) of the first group” or is/are “outwardly disposed”, “inwardly disposed” etc. are not to be understood in a restrictive manner such that the lumen(s) of the second group has/have to completely surround the lumen(s) of the first group, although this is a preferred embodiment of the invention. The case is also covered by the invention that, for example, only two lumens of the second group are provided which take up one or more lumens of the first group between them.

The change in the pressure is only one conceivable embodiment of the invention. The case is also covered by the invention that any other desired properties of the functional fluid can be influenced by the actuator. It is thus conceivable that the actuator is configured such that the volume flow and/or the temperature of the functional fluid can be changed by means of the actuator.

Furthermore, at least one sensor can be provided which is configured such that it determines at least one property of the functional fluid and/or of the transported fluid and/or of at least one lumen. It is thus conceivable that the pressure loss which is generated by the lumen(s) of the second group and which depends on the kink state is measured and that a property of the functional fluid such as its pressure is changed in dependence thereon.

It is also conceivable that the actuator is configured such that it changes the temperature of the functional fluid in dependence on the temperature of the transported fluid. It is thus also conceivable that, in addition to a passive thermal insulation by the outwardly disposed lumen(s), which can be filled with air, for example, for this purpose, an active heating or cooling takes place in that a hot or cold fluid, such as preheated air, is conducted through or is located in the outwardly disposed lumen(s).

As stated above, a conceivable embodiment of the invention comprises the actuator being configured such that it changes the pressure of the functional fluid in dependence on the flow resistance of one or more of the lumens of the second group. If it is determined that this flow resistance, i.e. the pressure loss present, exceeds a limit value, a conclusion can be drawn that a kinking of the tube is present. In this case, the actuator can increase the pressure to a predefined value or can at least increase it for so long until the flow resistance again lies in an acceptable range.

The functional fluid can, for example, be a gas such as compressed air or a liquid.

The present invention furthermore relates to the use of an apparatus in accordance with one of the claims 1 to 6 in a blood treatment device, in particular in a dialyzer. Such a use is, for example, conceivable to the extent that at least one tube or tube section is formed by a multi-lumen tube in accordance with the invention. This tube or tube section can, for example, form a component of or the total extracorporeal circuit of a blood treatment device.

If the multi-lumen tube(s) or its or their inner lumen belonging to the first group is connected to the patient, the advantage results that the mass which the patient carries on his arm is comparatively small since this lumen can be configured as thin-walled. A further advantage for the patient comprises the increased safety since—as stated above—a kinking of the tube can be effectively remedied in an automated manner by the actuator.

There is furthermore an advantage in that the required heating power for the blood treatment device, in particular for the dialyzer, is reduced since the outwardly disposed tubes form a thermal insulation.

The present invention furthermore relates to a blood treatment device, in particular to a dialyzer, having at least one extracorporeal circuit, with the blood treatment device being configured with at least one apparatus in accordance with one of the claims 1 to 6 and with the extracorporeal circuit being formed at least sectionally by the multi-lumen tube of the apparatus.

The present invention furthermore relates to a method of operating an apparatus in accordance with one of the claims 1 to 6, with the method comprising the step of changing at least one property of the functional fluid. As stated above, this property can be the temperature, the pressure, the flow speed or the volume flow, etc. of the functional fluid.

The method preferably comprises the step of increasing the pressure in at least one lumen of the second group when a kinking of the tube has been determined.

The kinking of the tube can be detected, for example, in that the functional fluid is conducted through at least one lumen of the second group and in that the pressure drop of the functional fluid in the throughflow is measured.

If the pressure drop exceeds a limit value or if the pressure drop increases over time, a conclusion of a kinking can be made.

It is conceivable within the course of this procedure that at least two lumens of the second group are connected to one another, with the functional fluid flowing through a lumen of the second group in a first direction and subsequently being diverted and flowing through a further lumen of the second group in a second direction opposite to the first direction and with the pressure drop of the functional fluid in the throughflow being measured. The dialyzer or another blood treatment device or device recognizes the loss-free throughflow. If thus a pressure increase occurs, a conclusion can be drawn that the tube is kinked.

At least one valve arrangement can be used to “short circuit”, i.e. to connect, the two or more than two lumens of the second group.

To end the kinking, it is conceivable that the pressure in the lumen of the second group is increased for so long until the pressure drop falls below a specific limit value. Alternatively to this, the pressure in the lumen of the second group can be increased up to a reaching of a predefined value at which it is assumed that kinking is no longer present.

The present invention furthermore comprises the transfer of information and/or energy by a property change of the functional fluid and preferably by a pressure change or by pressure pulses of the functional fluid.

The pressure in the lumen(s) of the second group can, for example, thus be used by pressure modulation as a line medium for signals or energy.

It is conceivable that at least one valve is provided that is arranged such that it is opened or closed by the property change of the functional fluid or that this is released by a discriminant triggered by the passage of the pressure value.

It is also conceivable that the method comprises the step of measuring the temperature of the fluid flowing through the lumen(s) of the first group and, in dependence thereon, a property change such as a change of the temperature of the functional fluid.

Further details and advantages of the invention will be explained in more detail with reference to an embodiment described in the following.

The embodiment relates to a dialyzer having an extracorporeal blood circuit which comprises one or more tubes which comprise(s) a multi-lumen tube in total or section-wise.

The tube has a single inner lumen which is flowed through by blood as well as a plurality of lumens which are arranged around it and surround the inner lumen. Six lumens of the second group can be provided overall, for example, which surround the central lumen.

The dialyzer furthermore has at least one actuator by means of which the pressure in the outer lumens can be changed. At least one pressure sensor is furthermore provided which detects the pressure of the functional fluid.

Provision is made in this respect that at least two of the outwardly disposed lumens are connected to or communicate with one another such that the functional fluid flows, starting from the dialyzer, through one of the second lumens, then undergoes a reversal of direction, and subsequently flows through another one of the second lumens back to the dialyzer. The pressure sensor detects the pressure loss over this flow path or at least the pressure at the end of the second lumen through which the functional fluid flows back to the dialyzer,

If it is detected that the pressure loss is too large, a conclusion is drawn on the kinking of the multi-lumen tube.

The dialyzer thereupon activates the actuator which increases the pressure in the outwardly disposed lumens, whereby the multi-lumen tube experiences a greater stability and the kink pint is effectively removed.

The functional fluid, which can be air or water, for example, can also take over other tasks such as the transfer of information between the patient and the dialyzer or the transfer of energy, for example for actuating a valve, etc. 

1. An apparatus comprising at least one multi-lumen tube, wherein the tube has a first group of lumens and a second group of lumens wherein the lumen(s) of the second group are arranged around the lumen(s) of the first group, and wherein the lumen(s) of the first group serve the transportation of at least one fluid, and wherein the lumen(s) of the second group is/are filled with at least one functional fluid, and wherein the apparatus furthermore comprises at least one actuator which is in communication with at least one of the second lumens and is configured such that at least one property of the functional fluid can be changed by means of the actuator.
 2. An apparatus in accordance with claim 1, characterized in that the actuator is configured such that the pressure and/or the volume flow and/or the temperature of the functional fluid can be varied by means of the actuator.
 3. An apparatus in accordance with claim 1, characterized in that at least one sensor is provided which is configured such that it determines at least one property of the functional fluid and/or of the transported fluid and/or of at least one lumen of the second group of lumens, with provision preferably being made that the actuator is in communication with the sensor and is configured such that the property change of the functional fluid is changed in dependence on the property measured by means of the sensor.
 4. An apparatus in accordance with claim 1, characterized in that the actuator is configured such that it changes the temperature of the functional fluid in dependence on the temperature of the transported fluid.
 5. An apparatus in accordance with claim 1, characterized in that the actuator is configured such that it changes the pressure of the functional fluid in dependence on the flow resistance of one or more lumens of the second group.
 6. An apparatus in accordance with claim 1, characterized in that the functional fluid is a gas or a liquid.
 7. Use of an apparatus in accordance with claim 1 in a blood treatment device, in particular in a dialyzer.
 8. A blood treatment device, in particular a dialyzer, having at least one extracorporeal circuit, characterized in that the blood treatment device is configured with at least one apparatus in accordance with claim 1; and in that the extracorporeal circuit is formed at least sectionally by the multi-lumen tube.
 9. A method of operating an apparatus in accordance with claim 1, with the method comprising the step of changing at least one property of the functional fluid.
 10. A method in accordance with claim 9, characterized in that the method comprises the step of increasing the pressure in at least one lumen of the second group when a kinking of the tube has been determined.
 11. A method in accordance with claim 10, characterized in that the kinking of the tube is detected in that the functional fluid is conducted through at least one lumen of the second group and the pressure drop of the functional fluid is measured on the throughflow, with provision preferably being made that at least two lumens of the second group are connected to one another, with the functional fluid flowing through a lumen in a first direction and subsequently through a further lumen in a second direction opposite to the first direction and with the pressure drop of the functional fluid being measured on the throughflow of both lumens.
 12. A method in accordance with claim 10, characterized in that the pressure of the functional fluid in the lumen(s) of the second group is increased for so long until the measured pressure drop falls below a specific limit value.
 13. A method in accordance with claim 9, characterized in that the method comprises the step of transferring information and/or energy by at least one property change of the functional fluid and preferably by a pressure change or by pressure pulses of the functional fluid.
 14. A method in accordance with claim 13, characterized in that at least one valve is provided which is arranged such that it is actuated by the property change of the functional fluid.
 15. A method in accordance with claim 9, characterized in that the method comprises the step of measuring the temperature of the fluid flowing through the lumen(s) of the first group and a property change of the functional fluid in dependence thereon. 